Messier 27

Discovered on July 12, 1764 by Charles Messier.

Messier: M27.

July 12, 1764. 27. 19h 49m 27s (297d 21' 41") +22d 04' 00"
Nebula without star, discovered in Vulpecula, between the two forepaws, & very near the star 14 of that constellation, of 5th magnitude according to Flamsteed; one can see it well with an ordinary telescope of 3.5-foot [FL]; it appears of oval shape, & it contains no star. M. Messier has reported its position on the chart of the Comet of 1779, which was engraved for the volume of the Academy of the same year. Observed again January 31, 1781. (diam. 4')

[Mem. Acad. for 1771, p. 445-446 (first Messier catalog)]
On July 12, 1764, I have worked on the research of the nebulae, and I have discovered one in the constellation Vulpecula, between the two forepaws, & very near the star of fifth magnitude, the fourteenth of that constellation, according to the catalog of Flamsteed: One sees it well in an ordinary refractor of three feet & a half [FL]. I have examined it with a Gregorian telescope which magnified 104 times: it appears in an oval shape; it doesn't contain any star; its diameter is about 4 minutes of arc. I have compared that nebula with the neighboring starwhich I have mentioned above [14 Vul]; its right ascension has been concluded at 297d 21' 41", & its declination 22d 4' 0" north.
[p. 456-457] 1764.Jul.12. RA: 297.21.41, Dec: 22. 4. 0.B, Diam: 0. 4. Nebula without stars in Vulpecula, between the two forepaws & very near to the star 14 of this constellation, according to Flamsteed.

Bode: Bode 67.

A nebula.

Koehler: Koehler No. 6

[Nebula] in the Fox at the chest, longitude 5deg [Aqr] [305d]: latitude 43deg north.

Caroline Herschel

September 30, 1782. Independently found M27 (see WH's note).
She saw it again on April 6 and July 23, 1783.

William Herschel

[1811: PT Vol. 1811, p. 226-336; here p. 285]
8. Of double Nebulae with joined Nebulosity In addition to the instances referred to in the preceding article [Of Nebulae which are brighter in more than one Place], of nebulae that have more than one centre of attraction I give the following list of what may be called double nebulae. (*) See [15 nebulae, including M27]

[Unpublished Observations of Messier's Nebulae and Clusters. Scientific Papers, Vol. 2, p. 653]
1782, Sept. 30. My sister discovered this nebula this evening in sweeping for comets; on comparing its place with Messier's nebulae we find it is his 27. It is very curious with a compound piece; the shape of it though oval as M. [Messier] calls it, is rather divided in two; it is situated among a number of small [faint] stars, but with this compound piece no star is visible in it. I can only make it bear 278. It vanishes with higher powers on account of its feeble light. With 278 the division between the two patches is stronger, because the intermediate faint light vanishes more.
1783, Aug. 2. A distant suspicion of its being all stars; I want light.
1784, July 19 (Sw. 241). This nebula I suppose to be a double stratum of stars of a very great extent. The ends next to us are not only resolvable nebulosity; farther on the nebulosity it is but barely resolvable, and ends at last in milky whitishness of the same appearance as that in Orion. The idea I form of the shape of the strata is this: -
[drawing follows]
These two being laid on each other, A on A and viewed from B, so as to have the small round end A foremost , may produce the appearance of this curious nebula.
1794, October 27. With 287, 7feet reflector, I see only two patches of light joined together, like tow nebulae without stars, running into one another. There are a few very small stars visible in it, but no more than what in the rest of the heavens are scattered about. They therefore are not connected with the nebula or nebulae.

John Herschel (1833): h 2060.

h 2060 = M 27.
Sweep 166 (Auguat 17, 1828)
RA 19h 52m 8.6s, NPD 67d 43m +/- (1830.0) [Right Ascension and North Polar Distance]
(See fig 26.) A nebula shaped like a dumb-bell, with the elliptic outline completed by a feeble nebulous light. Position of the axis of symmetry through the centres of the two chief masses = (by microm.) 30.0deg .. 60.0 deg nf..sp. The diam of the elliptic light fills a space nearly equal to that between the wires (7' or 8'). Not resolvable, but I see on it 4 destinct stars 1 = 12 m at the s f edge; 2 = 12.13 m, almost diametrically opposite; 3 = 13 m in the n p quarter, and 1 = 14.15 m near the centre. Place that of the centre.
(See fig 26.) A nebula shaped like a dumb-bell, with the elliptic outline completed by a feeble nebulous light. Position [angle] of the axis of symmetry through the centres of the two chief masses = (by micrometer) 30.0deg .. 60.0 deg nf..sp [North Following to South Preceding, NE to SW]. The diameter of the elliptic light fills a space nearly equal to that between the wires (7' or 8'). Not resolvable, but I see on it 4 destinct stars: 1 = 12 m at the south following [SE] edge; 2 = 12 to 13 m, almost diametrically opposite; 3 = 13 m in the north preceding [NE] quarter, and 1 [sic] = 14 to 15 m near the centre. Place given is that of the centre.

Sweep 90 (August 24, 1827)
RA 19h 52m 10.0s, NPD 67d 45m 11s (1830.0)
Place the most condensed part of the southern head; diameter in RA = 25.0s. A most extraordinary object; v B; an unresolved nebula, shaped something like an hour-glass, filled into an oval outline with a much less dense nebulosity. The central mass may be compared to a vertebra or a dumb-bell. The southern head is denser than the northern. One or two stars seen in it.
The place given is the most condensed part of the southern head; diameter in RA = 25.0s [6 1/4']. A most extraordinary object; very bright; an unresolved nebula, shaped something like an hour-glass, filled into an oval outline with a much less dense nebulosity. The central mass may be compared to a vertebra or a dumb-bell. The southern head is denser than the northern. One or two stars seen in it.

Sweep 267 (July 13, 1830)
RA 19h 52m 13.3s, NPD 67d 44m 7s (1830.0)
I showed a friend the oval filling up of the outline of this strange object as delineated in Sw[eep] 266, and he saw it well.

Sweep 266 (July 12, 1830)
RA 19h 52m 15.0s, NPD 67d 44m 14s (1830.0)
Like a double-headed shot or a dumb-bell. The light perfectly milky; the s p head is a v l brighter. The outline is filled up elliptically with a F nebulosity as in figure, which, I think leaves ansae as if inclined to form a ring. Two S st in it and many more near, one close to edge (No. 1 of Sw 166). A most amazing object. Position of greater axis of the elliptic outline = 117.1deg; of axis of symmetry 31.4deg (microm).
Like a double-headed shot or a dumb-bell. The light perfectly milky; the south preceding [SW] head is a very little brighter. The outline is filled up elliptically with a faint nebulosity as in figure, which, I think leaves ansae as if inclined to form a ring. Two small [faint] stars [are] in it and many more near, one close to edge (No. 1 of Sweep 166). A most amazing object. Position [angle] of greater axis of the elliptic outline is 117.1deg; of axis of symmetry 31.4deg (micrometer).

[Appendix]

[Figure on Plate X, Figure 26, No. 2060, M. 27, RA 19h 52m 12s, NPD 67d 44']
Fig. 26. Mess. 27. -

Smyth: DCCXXIX [729]. M27.

DCCXXIX. 27 M. Vulpeculae.
AR 19h 52m 39s, Dec N 22d 17'.1
Mean Epoch of Observation: 1834.62 [Aug 1834]
[with drawing]
This is the double-headed shot or dumb-bell nebula, on the Fox's breast, close to 14 Vulpeculae; it is about 7deg to the south-east of Beta Cygni, and nearly half-way between it and the Dolphin. This magnificient and singular object is situated in a crowded vicinity, where field after field is very rich. It was discovered in 1764, and described by Messier as an oval nebula without stars. My instruments, however, shows several, of which three, lying sp [south preceding, SW] and nf [north following, NE], nearly in the same direction with the dumb-bell, and 26s distant, following, are sufficiently remarkable: the two largest are of the 8 and 9 1/2 magnitude, and 6s apart, on an angle = 73deg, the latter having a small reddish telescopic companion nf [north following, NE].

Lord Rosse

[Phil. Trans. 1844, p. 321-324, drawing on plate XVIII, Fig. 26; on his observation with his 3-feet (36-inch) aperture telescope]
Plate XIX, fig. 26, on the contrary [to M1], is a difficult object [w.r.t. presumable resolution into stars, as Rosse thought]; it requires an extremely fine night and a tolerably high power; it is then seen to consist of innumerable stars [all background or foreground], mixed with nebulosity; and when we turn the eye from the telescope to the Milky Way, the similarity is so striking that it is impossible not to feel a pretty strong conviction that the nebulosity in both proceeds from the same cause.
..
[p. 323-324] In some instances, with increasing optical power, the resolvable character has become clearly developed, and in fig. 26, and a further increase of power has shown the object resolved.

John Herschel, General Catalogue: GC 4532.

GC 4532 = h 2060 = M27.
RA 19h 53m 29.3s, NPD 67d 39' 43.0" (1860.0) [Right Ascension and North Polar Distance]
!!!; vB; vL; BiN; iE (Dumbbell N). 13 observations by W. & J. Herschel.
Magnificient; very bright; very large; binuclear; irregularly extended (Dumbbell Nebula)
Remark: Figures in PT 1833 (JH 1833), plate ii, Fig. 26; PT 1844 (Lord Rosse 1844), plate xix, Fig. 26; PT 1850 (Lord Rosse 1850), plate xxxviii, Fig. 17; PT 1861 (Lord Rosse 1861), plate xxxi, Fig. 43; D'Arr. (D'Arrest's Inaugural dissertation and description of the Copenhagen Equatoreal, 1861); plate ii, Fig. 8.

Huggins

[On the Spectra of some of the Nebulae. Phil. Trans. Roy. Soc., Vol. 154 (1864), p. 437-444; here p. 441]
[No. 4532. 2060 h. 27 M. R.A. 19h 53m 29s.3. N.P.D. 67d 39' 43". Very bright; very large; irregularly extended. Dumb-bell.] In Vulpecula.
The light of this nebula, after passing through the prisms, remained concentrated in a bright line corresponding to the brightest of the three lines represented in fig. 5, Plate X. This line appeared nebulous at the edges. No trace of the other lines was perceived, nor was a faint continuous spectrum detected.
The bright line was ascertained, by a simultaneous comparison with the spectrum of the induction spark, to agree in position with the brightest of the lines of nitrogen.
Minute points of light have been observed in this nebula by Lord Rosse, Otto Struve, and others; the spectra of these bright points, especially if countinuous like those of stars, are doubtless invisible from excessive faintness.
By suitable movements given to the telescope, different portions of the image of the nebula formed in the telescope were caused successively to fall upon the opening of the slit, which was about 1/10 inch by 1/300 inch. This method of observation showed that the light from different parts of the nebula is identical in refrangibility, and varies alone in degree of intensity.

[p. 442]
It is obvious that the nebulae 37 H IV (NGC 3242), Struve 6 (NGC 6572), 73 H IV (NGC 6826), 1 H IV (NGC 7009), 57 M, 18 H. IV (NGC 7662) and 27 M. can no longer be regarded as aggregations of suns after the order to which our own sun and the fixed stars belong. We have with these objects to do no longer with a special modification only of our own type of suns, but find ourselves in the presence of objects possessing a distinct and peculiar plan of structure.
In place of an incandescent solid or liquid body transmitting light of all refrangibilities through an atmosphere which intercepts by absorption a certain number of them, such as our sun appears to be, we must probably regard these objects, or at least their photo-surfaces, as enormous masses of luminous gas or vapour. For it is alone from matter in the gaseous state that light consisting of certain definite refrangibilities only, as is the case with the light of these nebulae, is known to be emitted.

Lassell

[Memoirs of the Royal Astronomical Society, Vol. XXXVI (36)]
[Drawing on Plate IX, Fig. 35]

Dreyer (1877)

GC 4532, h. 2060 [M 27]. Drawings in Lassell, Plate IX, Fig. 35, in Secchi, Plate IV, Fig. 10, and in D'Arrest, S.N., p. 338.

Vol. VIII of the Annals of the Observatory of Harvard College, which was received at Birr Castle in the summer 1877, contains lithographs from drawings by Mr. Touvelot of the following Nebulae: GC 116 [M 31] (Pl. 33), 1179 [M 42] (Pl. 24, Woodbury type), 4230 [M 13] and 4294 [M92] (Pl. 25), 4355 [M20] (Pl. 32), 4447 [M57] (Pl. 34), 4532 [M27] (Pl. 35).

Dreyer: NGC 6853.

NGC 6853 = GC 4532 = h 2060; M 27.
RA 19h 53m 33s, NPD 67d 39.6' (1860.0) [Right Ascension and North Polar Distance]
!!!, vB, vL, biN, iE (Dumbbell); = M27
Magnificient, very bright, very large, binuclear, irregularly extended (Dumbbell).
Remark: Figures in P.T. 1833 [JH 1833], plate X, Fig. 26; P.T. 1844 [Lord Rosse 1844], plate XIX, Fig. 26; P.T. 1850 [Lord Rosse 1850], plate XXXVIII, Fig. 17; P.T. 1861 [Lord Rosse 1861], plate XXXI, Fig. 43; D'A. [D'Arrest's Inaugural dissertation and description of the Copenhagen Equatoreal, 1861]; plate II, Fig. 8; Lass. 2 [Lassell, Memoirs R.A.S. vol. xxxvi], plate IX, fig. 35.

Pease

[Radial Velocities of Six Nebulae, PASP Vol. 27, No. 161, p. 239-240 (12/1915)]
1. Dumbbell Nebula. -- The slit was set on the brightest knot in the nebula about 1 3/4 minutes of arc sp the nucleus. The exposure was 32 1/2 hours, extending over five nights. Four strong bright lines show; 5007, 4959, H Beta, H Gamma; no continuous spectrum shows. The radial velocity is -63 km [/s].

Curtis

[Descriptions of 762 Nebulae and Clusters photographed with the Crossley Reflector. Publ. Lick Obs., No. 13, Part I, p. 9-42]
NGC 6853, RA=19:55.3, Dec=+22:27. [Publ. Lick Obs.] Vol. VIII, Plate 60. M27; the ``Dumb-bell'' Nebula in Vulpecula. Planetary. 0 s.n.

[The Planetary Nebulae. Publ. Lick Obs., No. 13, Part III, p. 55-74]
[with Lick b/w photo, Fig. 11]
NGC 6853; 19h 55.3m; +22d 27'
The ``Dumb-bell'' Nebula in Vulpecula. Enlarged 5.3 times from a negative of 2h exposure time. Central star of magn. 12; 8'x4' in p.a. 125deg. One of the ``giants'' of the planetary class and of great importance in theories of planetary structure because of the easy visibility of intrinsic details. Rel. Exp. 20.